From 740ef15cbf40d8a0031ad8774a10b3711f4fcd54 Mon Sep 17 00:00:00 2001
From: Tony Garnock-Jones <tonygarnockjones@gmail.com>
Date: Fri, 1 Jun 2012 11:26:06 +0100
Subject: [PATCH] Better error ignoring; logging

---
 experiments/python/hop/relay.py | 33 +++++++++++++++++++++++----------
 1 file changed, 23 insertions(+), 10 deletions(-)

diff --git a/experiments/python/hop/relay.py b/experiments/python/hop/relay.py
index 6108afa..722fe56 100644
--- a/experiments/python/hop/relay.py
+++ b/experiments/python/hop/relay.py
@@ -15,6 +15,9 @@
 ## You should have received a copy of the GNU General Public License
 ## along with Hop.  If not, see <http://www.gnu.org/licenses/>.
 
+from __future__ import with_statement
+
+import logging
 import threading
 import socket
 
@@ -24,21 +27,25 @@ from dispatch import HopRelayMixin
 
 class HopRelay(HopRelayMixin):
     def __init__(self, in_ch, out_ch, ns = None, peer_address = None):
+        self.lock = threading.Lock()
         self.in_ch = in_ch
         self.out_ch = out_ch
         self.peer_address = peer_address
         self.thread = threading.Thread(target = self.relay_main)
         self.namespace = ns if ns else namespace.default_namespace
-        self.lock = threading.Lock()
         self.thread.start()
 
     def write(self, x):
-        try:
-            self.lock.acquire()
-            sexp.write_sexp(self.out_ch, x)
-            self.out_ch.flush()
-        finally:
-            self.lock.release()
+        if self.out_ch:
+            with self.lock:
+                try:
+                    sexp.write_sexp(self.out_ch, x)
+                    self.out_ch.flush()
+                except Exception:
+                    ## Don't care, here - we assume that any write
+                    ## error will be reflected in the socket closing
+                    ## in a little while in any case.
+                    pass
 
     def error(self, message, details):
         self.write(['error', message, details])
@@ -69,19 +76,25 @@ class HopRelay(HopRelayMixin):
         except EOFError:
             pass
         finally:
-            self.in_ch.close()
-            self.out_ch.close()
+            o = self.out_ch
+            i = self.in_ch
+            self.out_ch = None
+            self.in_ch = None
+            i.close()
+            o.close()
 
 class TcpRelayServer:
     def __init__(self, host = '0.0.0.0', port = 5671):
+        self.listen_address = (host, port)
         self.server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
         self.server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
-        self.server_socket.bind((host, port))
+        self.server_socket.bind(self.listen_address)
         self.server_socket.listen(4)
         self.thread = threading.Thread(target = self.listen_main)
         self.thread.start()
 
     def listen_main(self):
+        logging.info("Accepting connections on %r" % (self.listen_address,))
         while True:
             conn, addr = self.server_socket.accept()
             conn.send(sexp.format(['hop']))